you need to check the release notes, and compare the differences.
also check the Open MPI version in both of them.
In general it's not so good idea to run different versions of the software
for performance comparison or art all.
since both of them are Open source, backward computability is not always
promised ( IMHO ).
Lenny.

> Hi,
>
> I have two machines with RHEL 5.2, then I installed OFED 1.4.1 driver
> on the first machine, the second machine is using OFED 1.3.1 by RHEL
> owned. My question is if the different version of OFED drivers will
> affect performance?
>
> Thanks.
>
> Eric Lee
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